Document 1BeLge6eXRLx5By51oRmG6Ym

RREEMMEEDDFFIIRRAAOOLLMM AAAACCTTPFIIOOOORRNNMMSSEERRTTOOIINNAADDLLUULLSSEETTVVRRIIIIAAAATTLLEEWWGAAGRSSROTTOEUEUNNDDDDWWIIAASSTTPPEEOORRSSAALLPPOOSLLSIILLTTUUEETTIIOONN RREoonbbveeirrrttonmAA..entPPaaalsscchhEkkneeg,,ineSSeuurppieenrrgvviiss&oorrPollution Control SE33tM4n.vCCioorPmmoappnulama,nenynytMaNl Engineering 55133 & Pollution Control St. Paul, MN 55133 MEMiinccvhhiaareeollnmeAA..ntaSSlaannttEoonrrgooi,,neeMMraainnnaagggeerr& Pollution Control SE33tMnn.vciCoroPmomapnuplama,nenynytMaNl Engineering 55133 & Pollution Control St. Paul, MN 55133 ~ ABAallrllarann EGnG..g i nGGeeebbehhraairrnddg,, C~Vo/imicpceae nyPPrreesslideenntt.....:~-.............~"~.e~.<~...:.e..r .... ..... MBMaiirnnrnneeaaEppnooglliiinsse,,eriMMnNNg Company '` - ~..... ...... PPrreeppaarreedd ffoorr tthhee 5577tthh AAnnnnuuaall CCoonnffeerreennccee ooff tthhee WWaatteerr PPoolllluuttlioonn CCoonnttrrooll Federation Federation SSeepptteemmbbeerr 3300--OOccttoobbeerr 44,, 11998844. SSeessssiioonn 1155 NNeeww OOrrlleeaannss,, LLoouuiissiiaannaa 11331155..00000011 EExxhhiibbiitt 11331155 State of Minnesota v. 3M Co., Court File No. 27-CV-10-28862 IINNTTRROODDUUCCTTIIOONN AANNDD BACKGROUND BACKGROUND DDuurriinngg tthhee 11994400''ss aanndd 5500''ss,, sseevveerraall companies, companies, including including 3M, 3M, hired hired a a wwaassttee ddiissppoossaa~l ccoonnttrraaccttoorr to to dispose dispose of of waste waste materials materials from from their manufacturing plants. The approximately 60 acre disposal their manufacturing plants. The approximately 60 acre disposal ssiittee wwaass llooccaatteedd iinn aann uunnddeevveellooppeedd,, low low land land area area about about 10 miles i0 miles ffrroomm tthhee CCiittyy ooff SStt.. PPaauull,, MMiinnnneessoottaa,, in An what what is is now now the the City City of of OOaakkddaallee,, MMiinnnneessoottaa.. TThhee ssiittee iinncclluuddeedd a a bbuurrnn area area for for off/spec off/spec pprroodduuccttss aanndd ootthheerr vwaassttee mmaatteerriiaallss,, a a ddrruumm recycling recycling operation, operation, aanndd sseevveerraall wwaassttee ddiissppoossaall aarreeaass ffoorr both both organic organic and and inorganic inorganic rreessiidduueess.. OOrriiggiinnaallllyy,, ddiissppoossaall ooff the the vaste waste was was incidental incidental to to the the rum reconditioning and recycling operation. However, as the drum reconditioning and recycling operation. However, as the aammoouunntt aanndd vvoolluummee ooff wwaassttee increased, increased, the the waste waste disposal disposal activity activity ggrreeww aanndd tthhee ddiissppoossaall ccoonnttrraaccttoorr ffoouunndd iitt nneecceessssaarryy ttoo ddiissg~osbe~'Off ~"~~ wastes in trenches and other low areas in the site. By 1960, most wastes in trenches and other low areas in the site. By 1960, most of the available disposal areas on site were filled and the of the available disposal areas on site were filled and the disposal site contractor ceased operations. disposal site contractor ceased operations. SSiinnccee 11996600 tthhee ddiissppoossaall ssiittee bbeeccaammee ccoovveerreedd wwiitthh ffoolliiaaggee aanndd tthhee pprrooppeerrttyy cchhaannggeedd hhaannddsa,, aallll ooff wwhhiicchh oobbssccuurreedd tthhee ppaasstt uussaaggee.. AAfftteerr lleeaarrnniinngg aabboouutt tthhiiss ssiittee iInn 11997788 ffrroomm ssoommee ooff tthhee aarreeaa rreessiiddeennttss,, tthhee ssttaattee ppoolllluuttiioonn ccoonnttrrooll aaggeennccyy ccoonndduucctteedd aa pprreelliimmiinnaarryy iinnvveessttiiggaattiioonn aanndd nnoottiiffiieedd tthhee ppootteennttiiaallllyy rreessppoonnssiibbllee ppaarrttiieess iinn eeaarrllyy 11998800,, iinncclluuddiinngg pprreesseenntt aanndd ppaasstt llaanndd oowwnneerrss,, ttrraannssppoorrtteerrss aanndd wwaassttee ggeenneerraattoorrss.. 11331155..00000022 oe LL~etteerr in thee yyeeaarr,, tthhee rreessppoonnssiibbllee ppaarrttiieess wweerree ccaalllleedd ttoo ae meeting at the state pollution control agency to discuss a course meeting at of action. the In stthaeteabspeonlcluetioofnancyonstproecl ifagiecncpyroptoosadlissc,us3s1 apociontuerdse o action. In the absence of out. the need for an immediate atneychnaipcealcifiicnvepsrotipgoastailoan, o3Hf pthoeinsteidte aces to out. the need dete for rmine an immediate the scope of the prob technical lein m.ves3t4iga votilounnteoef rethde tomite area und to th e determine necessary the scope investiga toifontheandprowbiltehmt. he 3Happvrooluvanlteeorfedth eto fund the necessary investigation and state pollution control agency, Barr wEintghinetehreinagp,proavaMlinnofeaptohleis, state pollution control agency, Barr Engineering, Minnesots, based independent consulting firm, was ahiMriendnetaopocloinsd,uct Minnesota, based independent consulting firm, was hired to conduct tthhee tinnvveessttiiggaattiioonn iinn llaattee DDeecceemmbbeerr,, 1980. 1980. Prior to this Prior to this iinnvveessttiiggaattiioonn,, lliittttllee iinnffoorrmmaattiioonn was was available available on on wastes wastes that that were deposited in the mites, the hydrogeology of the area, and the were deposited in the sites, quality of surface water and the hydrogeology of groundwater in both the the asrheaal,loawndandthe qgueaelpietry siofte suarqfuaicfeersw.aterReacnodllegcrtoiuonndswatreergaridninbgoththethehisshtaolrlyowofantdhe deeper site aquifers. Recollections regarding the history of the ssiitteess vweerree ooftteenn ccoonnfflliiccttiinngg,, which Which mmaaddee iitt difficult difficult to .to develop develop ..... tthhee ssccooppee ooff tthhee iinnvveessttiiggaattiioonn.. 5 BBaasseedd oonn tthhee iinnffoorrmmaattiioonn that that was was available available and and on on the the suggestions suggestions of the state pollution control agency and other units of of the state pollution control agency and other government, the hydrogeologic investigation was udneistisgneofd to meet government, the hydrogeologic investigation was designed to meet tthhee ffoolllloowwiinngg objectives: objectives: 1. OObbttaaiinn aa ddeeffiinniittiioonn ooff tthhee ddiissppoossaall ssiittee lliimmiittse iinncclluuddiinngg tthhee I. llooccaattiioonnss ooff aarreeaass tthhaatt wweerree uusseedd ttoo ddiissppoossee ooff tthhee wwaasstteess.. 2. Define the site hydrogeology including directions of e Dgerfoiunnedvattheersimtoevemheyndtroganedolocghyaraincctleurdiiznagtiodnireocftitohnesunofderlying groundwater movement and characterization of the underlying ssooiillss aanndd bbeeddrroocckk in in tthhee vicinity vicinity of of the the site. site. 13113515..00000033 - 3. Determine the ccoonncceennttrraattiioonn and and extent of possible p08eible Determine the contamination in the soil and extent of grounduater beneath the disposal contamination in the soil and groundwater beneath the disposal site and in the surface water. site and in the surface water. 4. Recommend any further studies and/or remedial measures that 4. Recommend any further studies and/or remedial measures that would be warranted by the results of the investigation. would be warranted by the results o the investigation. Due to the limited information that was available on the disposal Due to the limited information that was available on the disposal sites, the description of the wastes and the hydrogeslogy of the sites, the description of the wastes and the hydrogeology of the area, a phased approach was used and the work scope was modified area, a phased as information afprpormoadcahta wacsolluescetdioannd acthteiviwtoireksscboepceamewasavamioldaibfliee.d as information from data collection activities became available. AA ttoottaall ooff 33 pphhaasseess wweerree rreeqquuiirreedd in in this this investigation investigation to to ......... tthhoorroouugghhllyy uunnddeerrssttaanndd tthhee ssiittee hhyyddrrooggeeoollooggyy aanndd ddeetteerrmmiinnee tthhee.......~=; 7 ~~'~~"~": eexxtteenntt ooff tthhee pprroobblleemm.. The work plan for each phase of the The work plan for each phase of the iinnvveessttiiggaattiioonn wwaass rreevviieevweedd aanndd aapppprroovveedd bbyy the the state state pollution pollution control agency, the U.S.EPA, other regulatory agencies, and the control agency, the U.S.EPA, other regulatory agencies, and the local units of government. local units of government. The first phase of the study involved the placement of deep The first phase of the study involved the placement of deep bedrock borings and a nusber of shallow monitoring ells and soil bedrock borings and a number of shallow monitoring wells and soil borings around the disposal site. Samples of soil and groundvater borings around the disposal site. Samples of soil and groundwater were analyzed to define the extent to which waste from the site were analyzed to define the extent to which waste from the site had migrated into the shallow groundwater. In addition, several had migrated into grounduater level the mea shallow surements groundwater. were taken to In addition, define the disreevecrtailon groundwater level measurements were taken to define the direction ooff ggrroouunnddwwaatteerr mmoovveemmeenntt iinn the the site site aquifers. aquifers. Evaluation of the Evaluation of the .... gata from this initial phase showed that additional study would be data from this initial phase showed that additional study would be required to further define the waste disposal areas, the site required to further define the waste disposal areas, the Bite ggeeoollooggyy,, aanndd tthhee eexxtteenntt ooff tthhee hhoorriizzoonnttaall and and vertical vertlca] migration migration of potential contaminants through the bedrock aquifers underlying of potential contaminants through the bedrock aqulfera underlying tthhee ssiittee.. 1311351.5.00000044 - The primary goal {n the final two phases of this study was to understand the mechanisms of contaminant migration from the shallow groundwater to the deep aquifers, and based on this knowledge, develop a remedial action plan that would remove the primary sources of contamination and control the movement of contaminants into the deep aquifers underlying the site. The results of the hydrogeologic investigation which was completed in April, 1983, are summarized in the next section of the paper. SSUUMMMMAARRYY OOFF PPHHAASSEE II,, IIII,, IIlI1l HHYYDDRROOGGEEOOLLOOGGIICC SSTTUUDDYY DDIISSPPOOSSAALL SSIITTEE LLIIMMIITTSS TToo ddeeffiinnee tthhee lliimmiittss ooff tthhee ddiissppoossaall ssiittee,, DDeeppaarrttmmeenntt ooff di TTrraannssppoorrttaattiioonn aaeerriiaall pphhoottooggrraapphhss ffrroomm tthhee pprreesseenntt ttiimmee bbaacckk ttoo tthhee mmiidd--11994400''ss wweerree rreevviieewweedd ffoorr eevviiddeennccee ooff ddiissppoossaall aaccttiivviittyy.. EEvviiddeennccee ooff wwaassttee ddiissppoossaall aaccttiivviittyy iiddeennttiiffiieedd oonn tthhee aaeerriiaall pphhoottooggrraapphhss iinncclluuddeedd bbuurriiaall ttrreenncchheess,, aarreeaass ooff ssuurrffaaccee ddiissppoossaall,, aanndd sseevveerraall bbuurrnneedd oovveerr aarreeaass.. OOnn tthhee bbaass~iss ooff tthh~iss ~innffoorrmmaattiloonn aanndd iinntteerrvviieewwss wwiitthh rreettiirreedd aanndd pprreesseenntt eemmppllooyyeeeess,, iitt wwaass ddeetteerrmmiinneedd tthhaatt tthheerree wweerree tthhrreeee sseeppaarraattee ddiissppoossaall aarreeaass.. FFiieelldd ssuurrvveeyyss wweerree ccaarrrriieedd oouutt ttoo ffuurrtthheerr ddeelliinneeaattee tthhee ssiitteess.. CCoommbbiinniinngg tthhee aaeerrilaall pphhoottooggrraapphh iinnffoorrmmaattiioonn wwiitthh tthhee ssiitteess ssuurrvveeyy ddaattaa hheellppeedd ttoo ddeeffiinnee tthhee bboouunnddaarriieess ooff tthhee tthhrreeee ddiissppoossaall smiitteess sshhoowwnn iinn FFiigguurree 1I.. TThhee tthhrreeee ssiitteess sshhoowwnn oonn tthhee mmaapp wweerree nnaammeedd tthhee AAbbrreesscchh,, BSrtoocckkmmaann,, aanndd EEbbeerrllee SSiitteess aafftteerr tthhee oowwnneerrss ooff tthhee ssiitteess astt tthhee ttiimmee ooff ddiissppoossaall sacctti~vvilttyy.. A& bbrriieeff hhiissttoorryy ooff eeaacchh ssiittee aanndd tthhee ttyyppeess ooff wwaassttee ddiissppoossaall aaccttiivviittiieess tthhaatt ooccccuurrrreedd aatt eeaacchh ssiittee ffoolllloowwss:: 11331155..00000055 sbresch Dispos] Site - This was the largest dispose site with an ares of about 50 acres. Initially, waste site with an ateposal vas area of limited about to the 50 acres. ZnltlalIy, moat southerly porti ow n aosfte disposal was limited to the most southerly portion of the site, near the former Abreach drum recycling the site, near the former &breech drum recycling operation. Aerial photographs indicate that wastes were operation. Aerial photographs indlcaLe thaL wastes were aduumnppeedd iinn sshhaallllooww ttrreenncchheess aanndd burned burned on on a a resuler regular bbaassiiss.. SSoommeettiimmee aafftteerr 1]995555 aanndd ccoonnttiinnuuiinngg uunnttiill nneeaarr tthhee eenndd ooff tthhee ssiittee uussee iinn 11996600,, surface surface vaste waste disposal disposal occurred in low lying areas and in several trenches occurred in low lying areas and in several trenches located on higher ground. A typical burial trench located on higher ground. A typical burial trench ggeenneerraallllyy aappppeeaarreedd ttoo aavveerraaggee aabboouutt 1100 ffeeeett iinn width, width, aabboouutt 115500 ffeeeett iinn lleennggtthh,, aanndd lliikkeellyy ddiidd nnoott exceed exceed 15 15 foot in depth. The burial of waste in trenches occurred feet in depth. The burial of waste in trenches occurred pprriinncciippaallllyy iinn tthhee nnoorrtthheerrnn portion portion of of the the site. site. (bepartment of Transportation records indicate that (Department of Transportation records indicate that wvaassttee wwaass eennccoouunntteerreedd dduurriinngg construction construction of of a a highway highway tthhrroouugghh tthhiiss ppoorrttiioonn ooff tthhee ssiittee..)) SSoommeettiimmee aafftteerr 1957 1957 iitt aappppeeaarrss tthhaatt mmoosstt ooff tthhee waste waste disposal disposal occurred occurred iimmmmeeddiiaatteellyy ssoouutthh ooff wwhhaatt is Is now now the the highway. highway. Because Because ooff tthhee sshhaallllooww ggrroouunndduwaatteerr ttaabbllee,, tthhee majority majority of of the the wwaassttee ppllaacceedd iinn tthhee AAbbrreesscchh ssiittee ssoouutthh ooff tthhee hhiigghhvwaayy vwaass lliikkeellyy ppllaacceedd oonn tthhee ggrroouunndd ssuurrffaaccee aanndd ppaarrttiisallllyy ccoovveerreedd wviitthh ssooiill.. IInn tthhee llaatteerr yyeeaarrss of of the the Abreach Abresch site. it appears that greater quantities of waste site, it appears that greater quantities of waste including domestic rubbish vere alec being deposited at including domestic rubbish were also being deposlte~ st tthhee ssiittee.. 1315.0006 - 1315.0006 ~Brroocckkmmaann DDiSseppoosaaall BSiittee -- 7Thhee aaeerrSiael] pphhoottooggrraapphhss iinnddiiccaattee tthhaatt wwaassttee ddiissppoossaall aaccttiivviittiieess eatt tthhee BBrroocckkmm~ann ssiittee bbeeggaann ssoom meettiimmee iinn tthhee 1~994400~'sa aannd8 eennddesd8 iSnn tthhee e eaarrllyy ~1995500'~ss.. T~hhee mmeetthhoodd oo~f wwaassttee ddiissppoossaall uusseedd aatt tthhee Brockman Brockman ssi~ttee fiss n noott rreeaaddiillyy aappppaarreenntt ffrroomm tthhee aaeerriiaall pphhoottooggrraapphhss.. TThhee aarreeaa ooff llaanndd aalltteerraattiloonn aatt tthhee BBrroocckkmmaann ss~ittee wwaass aapppprrooxxiimmaatteellyy 55 aaccrreess.. IInntteerrvviieewwss wwiitthh ppaasstt aanndd pprreesseenntt eemmppllooyyeeeess iinnddiiccaattee tthhaatt tthhee BBrroocckkmmaann ssiittee oofftteenn wwaass uusseedd wwhheenn ttrruucckkss ccoouulldd nnoott aacccceessss tthhee llooww llyyiinngg aarreeaass ooff tthhee AAbbrreesscchh ssiittee.. EEbbeerrllee DDiissppoossaall SSiittee -- TThhee EEbbeerrllee ssiittee wwaass uusseedd ffoorr tthhee ooppeenn bbuurrnniinngg ooff wwaassttee,, pprriimmaarriillyy ooffff--ssppeecc pprroodduuccttss aanndd sso0l1iidd wwaassttee,, aanndd nnoo eevviiddeennccee ooff ssuurrffaaccee ddiissppoossaall oorr . wwaassttee bbuurriiaall iinn ttrreenncchheess iiss eevviiddeenntt iinn t~hhee aaeerr:iiaall....../~i~ .... ~ pphhoottooggrraapphhss.. TThhee aarreeaa ooff llaanndd aalltteerraattiioonn aatt tthhee EEbbeerrllee ssiittee wwaass aapppprrooxxiimmaatteellyy 22 aaccrreess.. SSIITTEE HHYYDDRROOGGEEOOLLOOGGYY TToo ddeetteerrmmiinnee tthhee ddiirreeccttiioonn ooff ggrroouunnddwwaatteerr mmoovveemmeenntt aanndd ttoo cchhaarraacc-tteerriizzee tthhee uunnddeerrllyyiinngg ssooiillss aanndd bbeeddrroocckk iinn tthhee vviicciinniittyy ooff tthhee ssiittee,, sseevveerraall sshhaallllooww ssooilll bboorriinnggss aanndd ddeeeepp bbeeddrroocckk bboorriinnggss wveerree pPllaacceedd ~inn aanndd nneeaarr tthhee d~iissppoosaaall ssiitteess.. AAvvaaiillaabbllee hhyyadrrooggeeoollooggficc @daattaa,, iinncclluuddiinngg pprriivvaattee wweellll ddaattaa,, ccoonnssttrruuccttiioonn ssiittee bboorriinnggss aanndd iinnffoorrmmaattiioonn ffrroomm tthhee MMiinnnneessoottaa aanndd UU..SS.. GGeeoollooggiicc SSuurrvveeyyss wweerree uuttiilliizzeedd,, wwhheerree ppoossssiibbllee,, ttoo ooppttiimmiizzee tthhee bboorriinngg llooccaattiioonn aanndd pPrroovviiddee rreeffeerreennccee ddaattaa.. FFiigguurree 22 sshhoowwss tthhee llooccaattiioonnss ooff oonn--ssilttee bboorriinnggss aanndd wweellllss aanndd FFiigguurree 33 sshhoowwss tthhee llooccaatt~ioonn ooff ooffffssiettes 11331155..00000077 or borings and wells that were used to obtain groundwater levels in borings and wells that were used to obtain groundwater levela In the underlying backrock formations. These measurements were used the underlying backrock formations. These measurements were used to determine the direction of the groundwater movement in both the to determine the dlreetlon of the groundwater movement In both the sshhaallllooww aanndd ddeeeeppeerr ssiittee aaqquuiifeerrsS.o DDiissppoossaall SSiittee SSooiillss aanndd GGeeoollooggyy Soil borings placed during the investigation showed that the soils Soil borings placed during the investigation showed that the soils oovveerrllyyiinngg tthhee bbeeddrroocckk iinn tthhee vviicciinniittyy ooff tthhee ddiissppoossaall ssiitteess aarree complex and generally consist of alternating units of sandy to complex and generally consist of alternating units of sandy to clayey sandy alluvium and glacial till, which is a heterogeneous clayey sandy alluvium and glacial till, which is a heterogeneous ..... mmiixxttuurree ooff ssaanndd,, ssiilltt,, aanndd ccllaayy.. BBeeddrroocckk bboorriinnggss ppllaacceedd dduurriinngg tthhee iinnvveessttiiggaattiioonn indicated that limestone formation (Platteville limestone) underlies all three limestone formation (Platteville limestone) underlies all three ssiitteess.. BBeenneeaatthh tthhee EEbbeerrllee aann~d tthhee nnoorrtthheerrnn ppoorrttiioonn ooff tthhee AAbbrreesscchh ssiittee,, tthhee PPllaatttteevviillllee lliimmeessttoonnee iiss oovveerrllaaiinn bbyy aa sshhaallee llaayyeerr ((DDeeccoorraahh sshhaallee)) wwhhiicchh iiss aann aaqguuiittaarrdd wwhheerree iitt iiss pprreesseenntt.. TThhee Platteville limestone formation is approximately 20 to 35 feet Platteville limestone formation is approximately 20 to 35 feet ddeeeepp iinn tthhee aarreeaa aanndd iiss a a ssoouurrccee ooff ssuuppppllyy water water for for some some private private wweellllss tthhaatt ssttiillll eexxiisstt iinn tthhee aarreeaa ttoo ssuupppplleemmeenntt tthhee mmuunniicciippaall water supply. The Platteville is characterized by fractures and water supply. The Platteville is characterlzea by fractures and ssoolluuttiioonn cchhaannnneellss.. TThhee PPllaatttteevviillllee ffoorrmmaattiioonn iiss uunnddeerrllaaiinn bbyy aa 33--56 ffoooott llaayyeerr ooff sshhaallee ((GGlleennwwoooodd sshhaallee)).. TThhiiss ffoorrmmaattiioonn iiss ggeenneerraallllyy ccoonnssiiddeerreedd ttoo .... rreettaarrdd tthhee mmoovveemmeenntt ooff ggrroouunnddwwaatteerr ffrroomm tthhee PPllaatttteevviillllee lliimmeessttoonnee ttoo tthhee uunnddeerrllyy~inn~g bbeeddrroocckk aaqquuliffeerr~s.. 11331155..00000088 - Underlying the Glenwood shale is a sandstone (St. Peter sandstone) t~nder]ying the Glenwood shale is a sandstone (St. Peter sandstone) aatt aa ddeepptthh ooff aapppprrooxxiimmaatteellyy 110000 ffeeeett.. TThhiiss iiss aann iimmppoorrttaanntt aaqquuiiffeerr iinn tthhee SStt.. PPaauull aarreeas aanndd iiss uusseedd ffoorr iinndduussttrriiaall wweellllss aann~d aa lliimmiitteedd nnuummbbeerr ooff oollddeerr mmuunniicciippaall aanndd pprriivvaattee wweellllss.. TThhee SStt.. Peter sandstone is between 150-165 feet thick in the vicinity of Peter sandstone is between 150-165 feet thick in the vicinity of tthhee ddiissppoossaall ssiittee~s.. TThhee ffoorrmmaattiioonn uunnddeerrllyyiinngg tthhee SStt.. PPeetteerr ssaannddssttoonnee iiss aa ddoolloommiittiicc ffoorrmmaattiioonn ((PPrraaiirriiee dduu CChhiieenn ggrroouupp)) wwhhiicchh iiss cchhaarraacctteerriizzeedd bbyy ffrraaccttuurreess,, jjooiinnttss,, aanndd ssoolluuttiioonn cchhaannnneellss aanndd iiss aabboouutt tthhee 112255--113355 ffeeeett tthhiicckk iinn tthhee aarreeaa.. TThhee PPrraaiirriiee dduu CChhiieenn ggrroouupp iiss uunnddeerrllaaiinn bbyy aa ssaannddssttoonnee ((JJoorrddaann ssaannddssttoonnee)) wwhhiicchh iiss aa ccooaarrssee ttoo mmeeddiiuumm ggrraaiinn ~ssasn,dns~stto~nnee .aabboouutt 8800--8855 ....... ffeeeett tthhiicckk iinn tthhee aarreeaa.. BBeeccaauussee tthheerree iiss nnoo aaqquuiittaarrdd sseeppaarraattiinngg tthhee PPrraaiirriiee dduu CChhiieenn aanndd JJoorrddaann,, tthheeyy aarree oofftteenn ccoonnssiiddeerreedd ttoo bbee oonnee hhyyddrroollooggiicc uunniitt eevveenn tthhoouugghh tthhee rraattee ooff ggrroouunnddwwaatteerr mmoovveemmeenntt tthhrroouugghh tthhee ttwwoo uunniittss ccaann bbee ssiiggnniiffiiccaannttllyy ddiiffffeerreenntt.. TTooggeetthheerr,, tthheessee ttwwoo uunniittss ffoorrmm tthhee pprriimmaarryy bbeeddrroocckk aaqquuiiffeerr iinn tthhee SStt.. PPaauull aarreeaa aanndd aarree uusseedd aass aa ssoouurrccee ooff mmuunniicciippaall ppoottaabbllee wwaatteerr bbyy mmaannyy ssuubbuurrbbaann ccoommmmuunniittiieess.. BBeeccaauussee tthhee ggrroouunnddwwaatteerr ffllooww ssyysstteemmss ooff iinntteerreesstt iinn tthhiiss ssttuuddyy do nnoott aappppeeaarr ttoo iinnvvoollvvee ffoorrmmaattiioonnss bbeellooww tthhee JJoorrddaann ffoorrmmaattiioonn,, aanndd bbeeccaauussee nnoo wweellllss iinn tthhee vviicciinniittyy ooff tthhee ddiissppoossaall ssiitteess ppeenneettrraattee bbeellooww tthhee JJoorrddaann,, tthhee rreemmaaiinnddeerr ooff tthhee bbeeddrroocckk sseeqquueennccee iiss nnoott ddeessccrriibbeedd iinn tthhiiss ppaappeerr.. AA ggeeoollooggiicc ccoolluummnn iinn tthhee vviicciinniittyy ooff tthhee ddiissppoossaall ssiitteess sshhoowwiinngg tthhee pprreevviioouussllyy mmeennttiioonneedd ffoorrmmaattiioonnss aanndd tthheeiirr aapppprrooxxiimmaattee tthhiicckknneesssseess iiss sshhoowwnn iinn FFiigguurree 44.. 11331155..00000099 - Initially, during the early stages of the study there was a Initially, durin9 the early stages of the study there was a concern that a major bedrock valley might be located very near the concern that a major bedrock valley might be located very dear the disposal sites. If a bedrock valley did exist, the valley would disposal sites. If a bedrock valley did exist, the valley would penetrate the Glenwood shale and would be a direct route for penetrate the Glenwood shale and would be a direct route for contaminants to move into the deeper aquifers. However, deep contaminants to move into the deeper aquifers. However, deep bedrock borings and a detailed seismic study shoved that the major bedrock borings and a detailed seismic study showed that the major bedrock valleys in the disposal site area were approximately 3 bedrock valleys in the disposal site area were approximately 3 miles west and approximately 1 mile east of the disposal sites. miles west and approximately i mile east of the disposal sites. The generalized location of these major buried bedrock valleys and The generalized location of these major buried bedrock valleys and their proximity to the disposal sites are shown in Figure 5. their proximity to the disposal sites are shown in,F~,gure 5, .......... ~ GGrroouunndduwaatteerr MMoovveemmeenntt TThhee Gdaattaa ffrroomm tthhee sshhaallllooww mmoonnitoring wells ShowedERST the ~~ ddiirreeccttiioonn ooff ggrroouunnddwwaatteerr mmoovveemmeenntt iinn tthhee sshhaallllooww ggrroouunnddwwaatteerr bbeenneeaatthh tthhee AAbbrreesscchh aanndd tthhee BBrroocckkmmaann ssiitteess iiss ttoowwaarrdd tthhee ssmmaallll ssttrreeaammss aanndd ppoonnddss tthhaatt aarree llooccaatteedd iinn aanndd aaddjjaacceenntt ttoo tthhee ttwwoo ssiitteess.. TThhee ffllooww iinn tthhee sshhaallllooww ggrroouunnddwwaatteerr bbeenneeaatthh tthhee ssmmaallll EEbbeerrllee ssiittee iiss eeaasstteerrllyy.. DDoowwnnwwaarrdd mmoovveemmeenntt ooff ggrroouunnddwwaatteerr iiss occurring fron the surficial vater table to bedrock with rates of occurring from the surficial water table to bedrock with rates of vertical movement on the order of 1 to 3 feet per year. vertical movement on the order of I to 3 feet per year. The direction of grounduater movement in the Platteville limestone The direction of groundwater movement In the Platteville limestone wweass d@iiffffiiccuulltt ttoo ddeetteerrmmiinnee ssiinnccee tthhee ffllooww iias tthhrroouugghh ffrraaccttuurreedd zones and solution channels. Water level measurements and zones and solution channels. Water level measurements and groundwater quality data, however, indicated that flow through the groundwater quality data, however, indicated that flow through the Platteville as to the southwest from the sites. Vertical P~atteville was to the southwest from the sites. Vertical movement of water from the Platteville limestone to the underlying movement of water from the Platteville limestone to the underlylng St. Peter does not occur in the vicinity of the disposs] sites St. Peter does not occur in the vicinity of the disposal sites becouse of the Glenwood shele which acts as an aquitard between because of the Glenwood shale which acts as an squltard between 13113515..00001100 or "the two formations. Hater level measurements in the St. Peter [fie two f0Emati0ns. wells indicate that tW hea[gerr oulenvdweal temreamsouvreemmeenntts inIn th~ehe StS.t. PP eteetrer w saenldlsstoinnd eicnaetaer thethat sithtees is also toward the groundwater movement soinuththweestS.t. FPiegtuerre sandstone near the sites is also toward the southwest. Figure 6 shows the general groundwater movement in the shallow site shows the general groundwater movement in the shallow site aquifers and Figure 7 shows the generalized grounduater movement aquifers and Figure in the Platteville 7 shows limestone the and gethneerSatl.izePdetegrrousnadndwsattoenre.movement in the Platteville limestone and the St. Peter sandstone. GGRROOUUNNDDWWAATTEERR AANNDD SSUURRFFAACCEE WWAATTEERR QUALITY QUALITY Grounduater samples collected from shallow monitoring vells placed Groundwater samples collected from shallow monitoring within the limits of the disposal sites were analyzed wfeorllspospsliabcleed within the limits of the disposal sites were analyzed for possible ccoonnttaammiinnaannttss.. AAnnaallyyssiiss ooff tthhee ssaammpplleess indicated indicated that that the the contaminants in the shallow grounduater are mostly volatile ocrognatnaimcinasnotlsvenitns tahendshtahaltlowthegrohuingdhwesattercoanrceentmroasttliyonsvolaaretilperese.n.t.......... organic beneath solvents and the northern that the highest concentnatlons and a small southern portion of are the Abresch beneath the northern site. The extent of and the a small shallow csoonutthaemrinnanptortpilounme ofin thtehesAebreasrcehas site. The extent of the shallow contaminant plume in these areas iiss sshhoowwnn iinn FFiigguurree 88.. A typical analysis showing the types and A typical analysis showing the types and tthhee ccoonncceennttrraattiioonn ooff tthhee shallow shallow grounduater groundwater contaminants contaminants is is shown shown iinn TTaabbllee i1.. Samples taken around the perimeter of the Eberle, Samples taken around the perimeter of the Eberle, Borroocckknmaann aanndd AAbbrreesscchh ssiitteess indicate indicate that that little llttle lateral lateral migration migration of contaminants had occurred through the groundwater in the of contaminants shallow glacial dhradifto.ccurSraemdpletshrocuoglhlecttheedgrforuonmdwtahteersurinfactehevaters sihnaltlheow AgblraecalcshlanddrifBtr.ockSmaamnplseistescolslheocvteedd thfartomlotwhecosnucrfeancteratwiaotnesrs in of the Abresch and Brockman sites volatile organic compounds are psrheosweendt thiant thleowacmaolnlcenptornadtsions of volatile within the organic Abresch compounds site and in are the present small in str the eam tshmaatllflpowosnds within castua the Abreech rd from the site Abres c and in h site. the small stream that This data supports t flows he co nc lu sion eastward that the sfhraomllotwhe gArboruensdcwhatesritmeo.v.esThlisntdoattahe suppopnodrstsa~n_dthelecaovnesclutshieon that the shallow Abresch site via gthreounsdmwalalterstrmoevaems tointtohe teheastp.ondsSamanpdlesleatvaeksen thien Abresch site via the small stream to the east. Samples taken tthhilss ssttrreeaamm aa ffeeww miles miles from from the the Abresch Abresch site site show show no no evidence evidence of of . contamination. contamination. 1311351.5.00001111